Vacuum fuel-peed device



W. A. EDWARDS.

VACUUM FUEL FEED DEVICE. APPLICATION FILED MAR. 28, 1919.

1321,296. Patented Nov. 11, 1919.

6 cardarafiz? Wine:

1 leading from theupper. part of the annular I vide an improved construction in a'vacuum' reservoir being connected by a pipe, 3, for" siding v and State of Illinois, United States of S ES manna: orrren WILLIAM nnwnnns; OF CHICAGO, ILLINOIS, Assienon T0 ST'EWARTT-WABNIER SPEEDOMETER. cqnPoRA'rIoN, OF CHICAGO, ILLINOIS, A CORPORATION or VIRGINIA.

To all 'wh orn it may concern:

Be it known that I, WILLIAM A. Enwnnns, a subject'of the King of Great Britain, re-

at Chicago, .in. the county of Cook.

America, have invented certain new and" useful Improvements in Vacuum Fuel-Feed :Devices, of which'the following is a specification, reference being had to the accompanying drawings, forming a part thereof. The purpose of this invention is to profuel feed device for supplying. liquid fuel to the carbureter of an internal combustlon engine, which shall be simpler in construction than those heretofore employed. It consists in the elements and features. of con-- struction shown and described as set out in the claimsa In the drawing: v The figure is a vertical axial section io'f a fuel feed tank embodying this in.-

chamber or. reservoir, 2, of the device, said delivering the liquid fuel to the carbureter, and having an atmosphere vent pipe, 4,

. space'between the reservoir wall'and the.in'- teriorly suspended vacuum chamber. 6 1s the liquid fuel supply pipe leading from a low level main tank, not shown, into the vacuum chamber. 7 is the atmosphere inlet to the vacuum chamber formed in an 'upwardly extending fitting, 8, into which there is also connected the p1pe, 9, which constitutes the suction connection to the device from any suitable source of suction, as the intake manifold of the engine, not shown.

In the: vacuum chamber there is sltuated a" float device for'operating the atmosphere valve, 10, which carried on the stem, 11, of the'float device seating downwardly n the tapered mouth, 12, which is venturishaped. and thereby restricted at a point between the suction opening and the vacuum chamber of the atmosphere inlet passage, 7. 13 is a screen for the atmosphere inlet to protect it from the entrance of dust and dirt. The vacuum chamber discharges into the reserve chamber, 2,' through the d1scharge fitting, 14,'having the flap Valve, 15,

Specification of Letters Patent. Patented Nov. 11, 1919 Application filed March as, 1919.

. Serial. m5. 285, 787.

near the top of that chamber. The dimensions of the lower portion, 20,- of the float device are calculated to make its buoyancy suffic ent-to counterpoise the weight of the parts. which are carried by the float, com-' prising the float stem, the atmosphere valve, the upper float, member, and, when they are present, the liquid fuel supply controllin g valve and its operating connections, and the impact of the liquid thereon, so that when-said lower float memberis submerged,

the entire float device and all the parts carried by it tend to remain in any position 1n WhlCh they may be situated, that is, either with the: atmosphere valve open, or with that valve closed. The dimensions of the upper member of the float device, 21, are calculated so that its buoyancy when substantially submerged is sufficient to. force the atmosphere valve off its seat'against the maximum suct on which will beat any time operating in the vacuum chamber, said sue-r.

tion obviously tending to hold the atmosphere valveseated. The result of this float I construction which consists of two members vertically separated from each other in the vacuum chamber the lower one slightly overbala-ncing the weight of the parts carried, is that as the vacuum chamber fills,

the atmesphere valve being closed, the float being in its lower position and the suction operating through the suction connection to lift the liquid from the main low level supply-tank, no. movement of .the parts from the position shown in'the figure will occur until the liquid. rises high enough to submerge the upper float member to a depth. suflicient to cause the resulting buoyancy of.

that upper member to be equal to the suc-f tion hold on the atmosphere. valve; whereupon slight increase of the depthof submersion beyond that point causing thebuoyancy to exceed the suction hold onthe valve, will cause thevalve ,tobe snapped immediately away from ,its'seat, the float rising .the distance to which the upper member-has been submerged, carrylng the atmosphere valve that distance away from its seat and admitting the full atmospheric pressure to the vacuum chamber, overcoming the suction, which is admitted through a relatively small port as seen in the drawing, and thereby causing the vacuum chamber to drop its liquid contents through the fitting, 14, past the flap valve, 15, into the reserve chamber.

- As the vacuum chamber is thus emptied,

the level of the liquid falling therein will not cause any change in the position of the float device or the valves operated by it until the level has fallen toa point a little below the top of the loWer float member, 20,

so as to unsubmerge a portion of thatfloat 1 liquid level falls below this point the float 1 device will descend with the fall of the level; and when the atmosphere valve is near its seat, but before it reaches it, the suction pulling in the air past that valve will suck the valve to its seat a little before it would have reached'it'by the fall of the liquid, slightly depressing the float device;

but the valve being fully seated, the "full force of the suction will continue to hold iton its seat, and vacuum being produced in the vacuum chamber, the liquid Wlll "be tions already described. e

For the. purpose of the described a'ctlon,

- it is not essential that there should be any: valve controlling the {liquid fuel supply,

but such valve may be provided for certain advantages which it may alford, and may be operated by the float device. There is this advantage in having a retaining valve to close the fuel supply inlet while the vacuum chamber is being emptied into the reserve chamber; viz., that whereas in theabsence of such a valve the contents of the pipe leading from the main low tank to the vacuum chamber tends to fall back into the main tank and then would have to be lifted again when the vacuum chamber is next to be filled, if this can be prevented there is a slight gain in efficiency in that that amount of liquid does not have to be lifted over and over again at each action of the device. If, however, the check-valve which is, provided to retain the contents of the fuel supply conduit in the intervals of the suction action, is so positioned that it has to be lifted by the suction, it has usually been lifted from the mainlow level tank to refill that chamber, repeatingthe cycle of operavalveat each action. As seen in the drawings, the liquid fuel supply pipe is connected' for discharge upwardly through the bottom of the vacuum chamber, the inlet port, 22, being controlled by a valve, 23, carried on the stem of the float which is the member is partially unsubmerged, and then the float fallingfseats the atmosphere valve and opens the valve, 23, in the same falling movement, and at the instant at which the suction becomes dominant for lifting the liquid fuel from the low main tank. It will be evident that the liquid will not fall out of the pipe, 6, until it has completely evacuated the vacuum chamber; and this will never happen in the proper operation of the device when the engine is running, because the dominance ofthe suction which occurs as soon as the atmosphere valve closes and the valve, 23, is opened to cause the upward flow of the liquid into the vacuum chamber to recur at the instant at which the outflow from the vacuum chamber to the reserve chamber ceases, that is, when the liquid level in the vacuum chamber hasfallen so as to only partly unsubmerge the lower float found that the loss due to the additionalrequirement of suction necessary to li-ft such member.

The connection of the valve, 23, with the float so as to be oscillated for seating by the rising of the float, has the further advantage that in case of the vehicle whose engme is supplied by the device descending a grade so stee that the main supply tan at the rear of t e vehicle is higher than the,

vacuum chamber, so that the lattermight be filled and even flooded and caused to overflow by gravity flow from the main tank. a

v The rise of the float in the vacuum chamber consequent upon said chamber bein filled to the proper high level, seats the va ve, 23,

and prevents further inflow from the main" tank.

lt is preferred to make the entrance 'pas- I I sage from the pipe, 6, into, the vacuum chamber of venturi form, as shown, with the more abruptly tapered mouth toward the valve, because it has been found that this form of passage ofl'ers a minimum resistance to the inflow of the liquid, which when the dimensionsare properly proportioned will be discharged through the constricted, substantially.

throat of the venturi passage, as rapidly as it would be discharged through a passage of the full width of the widened mouth of said venturi passage.

J 1. A'vacuum fuel feed device comprising a chamber having Q a suctlon connect on, an

atmosphere inlet andja liquid fuel supply connection; a valve to control the atmos- Q phere inlet; a float devicein the chamber operates the atmospherevalve; said float de vice comprising two buoyant portions at dif-.

ferentlevels a substantial distance apartin said chamber, -,the lower of said float por- 'ltions beingadapted-as to buoyancy to' coun- -terbalance the weightnofthevalve and .all '15 partsmoving with it, andvthe other portion of the float being adapted as to. buoyancy to overcome the suction on the valve.

2. In" a vacuumfuel feed device such asdefined in claiml foregoing, the suction connection openinglinto the atmosphere inlet passage ata point near the port'at' which the valve is-seated, jsaidv passage being restricted relatively to said port between said a suction-opening and the -vacuum chamber;

-- a valve" whichcontrols *the'liquid fuel inlet, p

any hand atChicago, Illinois, this 24th day March-I919; 1v f f WILLIAM EDWARDS- 3. In 'a'device such as defined in claim 1,

and connections byvvhich' the float seats said valve byits rising nio'v'ementfi v 4. In the construction'ldefined by. claim 1,

valve which'co'ntrols thehquid fuel inlet 1 float seats sald valve by the rising the descending movement and closed by the positioned with;respect toits seat for seating upwardl and connections by which the movement of the float.

5. Inithe construction defined in claim 1,

p 'j a valve which controlsthe liquid fuel inlet, actuated by change of. liquid level in thechamber, and connections by which the float positioned with respect to its seat for seating .with the inflow, and connections by which the float operates said valve for openingby the falling of the float; whereby in the intervals between the inflow said valve is -l1eld seated by the buoyancy of the lower member thereof alone without the assistance of the'upper member.

7. In the construction'defined in claim '1, the liquid fuel inlet being at the lower part of the vacuum chamber and of venturi form, a valve controlling said inlet and connections-by which said valve is openedby rising movement of the float.

In testimony whereof, I have hereuntoset 

